Merge remote-tracking branch 'origin/main' into balalaika

crates/maestro-cli/src/cli.rs

@@ -92,6 +92,14 @@ pub struct SpawnArgs {
     /// there.
     #[arg(long)]
     pub existing_branch: bool,
+    /// Run a Claude Code or Codex session in a plain terminal instead of the
+    /// structured (ACP) view it otherwise gets by default.
+    #[arg(long, conflicts_with = "structured")]
+    pub terminal: bool,
+    /// Ask for the structured (ACP) view explicitly. Only Claude Code and
+    /// Codex commands have an adapter; the daemon refuses anything else.
+    #[arg(long)]
+    pub structured: bool,
     /// After spawning, attach immediately.
     #[arg(long, short = 'a')]
     pub attach: bool,

crates/maestro-cli/src/sessions.rs

@@ -3,7 +3,7 @@
 use std::collections::HashMap;
 use std::io::Write;
 
-use maestro_protocol::display::abbreviate_dir;
+use maestro_protocol::display::{abbreviate_dir, supports_structured_view};
 use maestro_protocol::{
     ActivityState, ClientError, CreateSessionRequest, DaemonClient, DaemonInfo, SendInputRequest,
     Session, SessionStatus, SessionView, WorktreeSpec,
@@ -51,7 +51,7 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     };
 
     let body = CreateSessionRequest {
-        view: Default::default(),
+        view: spawn_view(&args),
         cwd: args.cwd.clone(),
         command: args.command.clone(),
         env,
@@ -61,6 +61,22 @@ pub async fn run_spawn(client: &DaemonClient, args: SpawnArgs) -> Result<Session
     client.create_session(&body).await
 }
 
+/// The view a `maestro spawn` asks for: structured whenever the command
+/// resolves to an agent with an ACP adapter, since that is the richer session
+/// and the one both other clients now default to. `--terminal` opts out;
+/// `--structured` forces the request through even for a command this side
+/// does not recognise, leaving the refusal to the daemon.
+fn spawn_view(args: &SpawnArgs) -> SessionView {
+    if args.terminal {
+        return SessionView::Terminal;
+    }
+    if args.structured || supports_structured_view(&args.command) {
+        SessionView::Structured
+    } else {
+        SessionView::Terminal
+    }
+}
+
 /// `maestro kill`. A forced kill (#81) retains the guarded worktree instead
 /// of removing it; the outcome names what was kept so dispatch can say where
 /// the work went.
@@ -239,6 +255,62 @@ mod tests {
 
     use super::DaemonInfo;
 
+    use clap::Parser;
+
+    use crate::cli::{Cli, Command};
+
+    fn spawn_args(extra: &[&str]) -> crate::cli::SpawnArgs {
+        let mut argv = vec!["maestro", "spawn", "--cwd", "/tmp", "--command"];
+        argv.extend_from_slice(extra);
+        let cli = Cli::try_parse_from(argv).expect("parses");
+        let Command::Spawn(args) = cli.command else {
+            panic!("expected spawn")
+        };
+        args
+    }
+
+    /// The CLI follows the two interactive clients: a command with an ACP
+    /// adapter spawns structured unless `--terminal` says otherwise, and
+    /// `--structured` still forces the request for a command this side does
+    /// not recognise.
+    #[test]
+    fn spawn_defaults_to_structured_for_supported_agents() {
+        use super::spawn_view;
+        assert_eq!(
+            spawn_view(&spawn_args(&["claude"])),
+            SessionView::Structured
+        );
+        assert_eq!(
+            spawn_view(&spawn_args(&["npx codex exec"])),
+            SessionView::Structured
+        );
+        assert_eq!(spawn_view(&spawn_args(&["bash"])), SessionView::Terminal);
+        assert_eq!(
+            spawn_view(&spawn_args(&["claude", "--terminal"])),
+            SessionView::Terminal
+        );
+        assert_eq!(
+            spawn_view(&spawn_args(&["opencode", "--structured"])),
+            SessionView::Structured
+        );
+    }
+
+    #[test]
+    fn spawn_refuses_both_view_flags_at_once() {
+        let err = Cli::try_parse_from([
+            "maestro",
+            "spawn",
+            "--cwd",
+            "/tmp",
+            "--command",
+            "claude",
+            "--structured",
+            "--terminal",
+        ])
+        .unwrap_err();
+        assert!(err.to_string().contains("--terminal"), "{err}");
+    }
+
     fn session(cwd: &str, command: &str, id: u128) -> Session {
         Session {
             view: Default::default(),

crates/maestro-daemon/src/local_api.rs

@@ -12,7 +12,8 @@
 
 use std::sync::Arc;
 
-use axum::extract::{Path, Query, State};
+use axum::body::Bytes;
+use axum::extract::{DefaultBodyLimit, Path, Query, State};
 use axum::http::StatusCode;
 use axum::response::{IntoResponse, Response};
 use axum::routing::{any, delete, get, post};
@@ -70,6 +71,10 @@ pub fn router(state: LocalApiState) -> Router {
         .route(routes::patterns::STRUCTURED, any(structured_ws))
         .route(routes::patterns::STRUCTURED_REPLAY, get(structured_replay))
         .route(routes::patterns::STRUCTURED_PROMPT, post(structured_prompt))
+        .route(
+            routes::patterns::STRUCTURED_ATTACHMENT,
+            post(structured_attachment).layer(DefaultBodyLimit::max(20 * 1024 * 1024)),
+        )
         .route(routes::patterns::STRUCTURED_CANCEL, post(structured_cancel))
         .route(routes::patterns::STRUCTURED_CONFIG, post(structured_config))
         .route(
@@ -432,6 +437,46 @@ async fn structured_replay(
     }
 }
 
+#[derive(Deserialize)]
+struct AttachmentQuery {
+    name: String,
+}
+
+async fn structured_attachment(
+    State(s): State<LocalApiState>,
+    Path(id): Path<Uuid>,
+    Query(query): Query<AttachmentQuery>,
+    bytes: Bytes,
+) -> Response {
+    let name = query.name;
+    if name.is_empty()
+        || name.len() > 180
+        || name == "."
+        || name == ".."
+        || name
+            .chars()
+            .any(|c| c.is_control() || c == '/' || c == '\\')
+    {
+        return error_response(
+            StatusCode::BAD_REQUEST,
+            "invalid_filename",
+            "use a filename without directory separators, up to 180 bytes",
+        );
+    }
+    match s.manager.store_acp_attachment(id, &name, &bytes).await {
+        Ok(Some(path)) => Json(serde_json::json!({ "path": path })).into_response(),
+        Ok(None) => error_response(
+            StatusCode::CONFLICT,
+            "not_structured",
+            "session is not a live structured session",
+        ),
+        Err(e) => {
+            let info = e.to_error_info();
+            error_response(session_error_status(&info.code), &info.code, &info.message)
+        }
+    }
+}
+
 async fn structured_prompt(
     State(s): State<LocalApiState>,
     Path(id): Path<Uuid>,

crates/maestro-daemon/src/session.rs

@@ -604,6 +604,36 @@ impl SessionManager {
         Ok(Some(replay))
     }
 
+    /// Store attachment bytes for a live structured session.
+    pub async fn store_acp_attachment(
+        &self,
+        id: Uuid,
+        name: &str,
+        bytes: &[u8],
+    ) -> Result<Option<std::path::PathBuf>, SessionError> {
+        {
+            let sessions = self.inner.sessions.lock().await;
+            let record = sessions.get(&id).ok_or(SessionError::NotFound(id))?;
+            if !record.is_live_structured() {
+                return Ok(None);
+            }
+        }
+        let dir = self.inner.sidecar.dir().join(format!("{id}.attachments"));
+        tokio::fs::create_dir_all(&dir).await?;
+        let dir = tokio::fs::canonicalize(dir).await?;
+        let path = dir.join(format!("{}-{name}", Uuid::new_v4()));
+        let mut file = tokio::fs::OpenOptions::new()
+            .write(true)
+            .create_new(true)
+            .mode(0o600)
+            .open(&path)
+            .await?;
+        use tokio::io::AsyncWriteExt;
+        file.write_all(bytes).await?;
+        file.sync_all().await?;
+        Ok(Some(path))
+    }
+
     /// Subscribe to the two projections of a structured session's ACP log.
     ///
     /// The transcript snapshot and whole reduced state are folded once by the

crates/maestro-daemon/tests/local_api.rs

@@ -234,6 +234,60 @@ async fn structured_ws_sends_snapshot_then_live_projection() {
     );
 }
 
+#[tokio::test]
+async fn structured_attachments_preserve_bytes_and_reject_paths() {
+    let h = spawn("attachments").await;
+    let fake = FakeAcp::new();
+    let id = structured_session(&h, &fake).await;
+    let client = reqwest::Client::new();
+    let endpoint = url(
+        h.addr,
+        &format!("/api/sessions/{id}/structured/attachments"),
+    );
+    let bytes = vec![0, 255, 10, 13];
+    let response = client
+        .post(&endpoint)
+        .query(&[("name", "sample.bin")])
+        .body(bytes.clone())
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 200);
+    let body: serde_json::Value = response.json().await.unwrap();
+    let path = body["path"].as_str().unwrap();
+    assert!(Path::new(path).is_absolute());
+    assert_eq!(std::fs::read(path).unwrap(), bytes);
+    for name in ["../escape", "a/b", "a\\b", "..", ""] {
+        let response = client
+            .post(&endpoint)
+            .query(&[("name", name)])
+            .body("text")
+            .send()
+            .await
+            .unwrap();
+        assert_eq!(response.status(), 400, "{name}");
+    }
+    let response = client
+        .post(&endpoint)
+        .query(&[("name", "large.bin")])
+        .body(vec![0; 20 * 1024 * 1024 + 1])
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 413);
+    let response = client
+        .post(url(
+            h.addr,
+            &format!("/api/sessions/{}/structured/attachments", Uuid::new_v4()),
+        ))
+        .query(&[("name", "file.txt")])
+        .body("text")
+        .send()
+        .await
+        .unwrap();
+    assert_eq!(response.status(), 404);
+}
+
 #[tokio::test]
 async fn structured_prompt_rejects_a_second_in_flight_turn_and_cancel_clears_it() {
     let h = spawn("naps-laptop").await;

crates/maestro-protocol/src/display.rs

@@ -226,6 +226,15 @@ pub fn command_tool(command: &str) -> Option<&'static str> {
         .map(|(_, tool)| *tool)
 }
 
+/// Whether a command line resolves to an agent Maestro can run as a
+/// structured (ACP) session — Claude Code or Codex, the two adapters
+/// `docs/STRUCTURED-VIEW.md` lists. Every client gates its structured-view
+/// control on this, and the daemon rejects a `Structured` request for
+/// anything else, so the answer has to come from one place.
+pub fn supports_structured_view(command: &str) -> bool {
+    matches!(command_tool(command), Some("claude" | "codex"))
+}
+
 /// [`resolve`]'s outcome: the tokenized command line, and the index within it
 /// of the word that is the actual program (past every assignment/wrapper it
 /// resolved through).
@@ -1064,4 +1073,14 @@ mod tests {
         assert_eq!(tokenize("\"FOO=1\" claude").unwrap()[0].plain_eq, None);
         assert_eq!(tokenize("FOO\\=1 claude").unwrap()[0].plain_eq, None);
     }
+
+    #[test]
+    fn structured_view_support_follows_the_resolved_program() {
+        assert!(supports_structured_view("claude --resume"));
+        assert!(supports_structured_view("FOO=1 /usr/local/bin/codex exec"));
+        assert!(supports_structured_view("npx claude-code"));
+        assert!(!supports_structured_view("opencode"));
+        assert!(!supports_structured_view("bash -l"));
+        assert!(!supports_structured_view("claude-code-acp"));
+    }
 }

crates/maestro-protocol/src/routes.rs

@@ -86,6 +86,11 @@ pub fn structured_prompt(id: Uuid) -> String {
     format!("{SESSIONS}/{id}/structured/prompt")
 }
 
+/// `POST /api/sessions/:id/structured/attachments` — upload a file.
+pub fn structured_attachment(id: Uuid) -> String {
+    format!("{SESSIONS}/{id}/structured/attachments")
+}
+
 /// `POST /api/sessions/:id/structured/cancel` — cancel an ACP turn.
 pub fn structured_cancel(id: Uuid) -> String {
     format!("{SESSIONS}/{id}/structured/cancel")
@@ -113,6 +118,7 @@ pub mod patterns {
     pub const STRUCTURED: &str = "/api/structured/:id";
     pub const STRUCTURED_REPLAY: &str = "/api/sessions/:id/structured/replay";
     pub const STRUCTURED_PROMPT: &str = "/api/sessions/:id/structured/prompt";
+    pub const STRUCTURED_ATTACHMENT: &str = "/api/sessions/:id/structured/attachments";
     pub const STRUCTURED_CANCEL: &str = "/api/sessions/:id/structured/cancel";
     pub const STRUCTURED_CONFIG: &str = "/api/sessions/:id/structured/config";
     pub const STRUCTURED_APPROVAL: &str = "/api/sessions/:id/structured/approvals/:nonce";

crates/maestro-tui/src/draft.rs

@@ -41,7 +41,7 @@ use std::time::{Duration, Instant};
 
 use chrono::{DateTime, Utc};
 use maestro_config::{builtin_presets, custom_preset};
-use maestro_protocol::display::{abbreviate_dir, command_tool};
+use maestro_protocol::display::{abbreviate_dir, supports_structured_view};
 use maestro_protocol::{
     BranchInfo, CreateSessionRequest, Project, SessionView, SpawnPreset, WorktreeSpec,
 };
@@ -255,9 +255,14 @@ pub struct DraftPane {
     /// "Advanced options" disclosure (#93). Closed by default — most spawns
     /// take the default target.
     pub advanced_collapsed: bool,
-    /// ACP-backed structured transcript. Off by default and supported only
-    /// when the resolved command is Claude Code or Codex.
+    /// ACP-backed structured transcript. Supported only when the resolved
+    /// command is Claude Code or Codex, and on by default whenever it is —
+    /// until the operator works the toggle themselves.
     pub structured_view: bool,
+    /// Set once the operator toggles structured view by hand. From then on a
+    /// command change never re-enables what they turned off, the same guard
+    /// `name_touched` gives the name field.
+    pub structured_view_touched: bool,
     /// Enclosing repository of the chosen target — from the project scan for
     /// picked rows, `/api/gitroot` for raw paths. `None` until known.
     pub base_repo: Option<PathBuf>,
@@ -298,7 +303,7 @@ impl Default for DraftPane {
         // while its data loads, and stay usable when the daemon reports none.
         let mut presets = builtin_presets();
         presets.push(custom_preset());
-        Self {
+        let mut draft = Self {
             id: NEXT_DRAFT_ID.fetch_add(1, std::sync::atomic::Ordering::Relaxed),
             presets,
             selected_preset: 0,
@@ -319,6 +324,7 @@ impl Default for DraftPane {
             worktree_enabled: true,
             advanced_collapsed: true,
             structured_view: false,
+            structured_view_touched: false,
             base_repo: None,
             probed_cwd: None,
             probe_seq: 0,
@@ -337,7 +343,11 @@ impl Default for DraftPane {
             // straight away, and Tab from here reaches the command tiles.
             focused_field: DraftField::DirPicker,
             home_dir: String::new(),
-        }
+        };
+        // The built-in tile the form opens on decides whether structured view
+        // starts ticked, exactly as a later preset list would.
+        draft.sync_structured_view();
+        draft
     }
 }
 
@@ -356,7 +366,7 @@ impl DraftPane {
             .position(|p| !p.command.is_empty())
             .unwrap_or(0);
         self.apply_seed_command();
-        self.clear_unsupported_structured_view();
+        self.sync_structured_view();
     }
 
     /// Land a seeded command on the tile that runs it: its own preset when the
@@ -673,18 +683,24 @@ impl DraftPane {
     }
 
     fn supports_structured_view(&self) -> bool {
-        matches!(command_tool(self.command()), Some("claude" | "codex"))
+        supports_structured_view(self.command())
     }
 
-    fn clear_unsupported_structured_view(&mut self) {
+    /// Re-resolve the toggle after the command changed: an unsupported
+    /// command forces it off, a supported one turns it back on unless the
+    /// operator has already made the choice themselves.
+    fn sync_structured_view(&mut self) {
         if !self.supports_structured_view() {
             self.structured_view = false;
+        } else if !self.structured_view_touched {
+            self.structured_view = true;
         }
     }
 
     pub fn toggle_structured_view(&mut self) {
         if self.supports_structured_view() {
             self.structured_view = !self.structured_view;
+            self.structured_view_touched = true;
         }
     }
 
@@ -827,7 +843,7 @@ impl DraftPane {
         }
         self.selected_preset =
             ((self.selected_preset as i32) + delta).rem_euclid(len as i32) as usize;
-        self.clear_unsupported_structured_view();
+        self.sync_structured_view();
     }
 
     /// Step-one boxes surviving the type-to-filter, in display order. A
@@ -1130,7 +1146,7 @@ impl DraftPane {
                     DraftField::Preset | DraftField::Submit => {}
                     DraftField::CustomCommand => {
                         self.custom_command.handle_key(other);
-                        self.clear_unsupported_structured_view();
+                        self.sync_structured_view();
                     }
                     // Typing filters the list; the highlight resets to the top
                     // so a narrowed search always starts at its best match.
@@ -1888,7 +1904,7 @@ mod tests {
     }
 
     #[test]
-    fn structured_view_is_default_off_and_visible_for_supported_agents() {
+    fn structured_view_is_default_on_and_visible_for_supported_agents() {
         let mut draft = DraftPane {
             advanced_collapsed: false,
             ..DraftPane::default()
@@ -1910,13 +1926,11 @@ mod tests {
                 command: "opencode".into(),
             },
         ]);
-        assert!(!draft.structured_view);
+        assert!(draft.structured_view, "on by default for a supported agent");
         assert!(draft.field_order().contains(&DraftField::StructuredToggle));
         let rendered = render_to_string(100, 24, |f| draft.render(f, f.area(), true));
-        assert!(rendered.contains("[ ] structured view"), "{rendered}");
+        assert!(rendered.contains("[x] structured view"), "{rendered}");
 
-        draft.toggle_structured_view();
-        assert!(draft.structured_view);
         draft.cycle_preset(1);
         assert_eq!(draft.command(), "codex");
         assert!(
@@ -2006,16 +2020,16 @@ mod tests {
             };
             draft.selected_preset = draft.presets.len() - 1;
             draft.custom_command = crate::text_input::TextInput::with_value(command);
+            draft.sync_structured_view();
 
             assert_eq!(
                 draft.field_order().contains(&DraftField::StructuredToggle),
                 supported,
                 "toggle visibility for {command:?}"
             );
-            draft.toggle_structured_view();
             assert_eq!(
                 draft.structured_view, supported,
-                "toggle takes effect for {command:?}"
+                "default selection for {command:?}"
             );
             let view = draft.build_request().unwrap().view;
             assert_eq!(
@@ -2027,6 +2041,12 @@ mod tests {
                 },
                 "request view for {command:?}"
             );
+
+            draft.toggle_structured_view();
+            assert!(
+                !draft.structured_view,
+                "the toggle turns the default off for {command:?}"
+            );
         }
     }
 
@@ -2061,7 +2081,6 @@ mod tests {
 
         assert_eq!(draft.command(), "npx claude-code --resume");
         assert!(draft.field_order().contains(&DraftField::StructuredToggle));
-        draft.toggle_structured_view();
         assert!(draft.structured_view);
         assert_eq!(draft.build_request().unwrap().view, SessionView::Structured);
 
@@ -2080,6 +2099,43 @@ mod tests {
         assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
     }
 
+    /// The default only applies until the operator has an opinion: once they
+    /// untick the box, moving between supported commands leaves it unticked
+    /// instead of turning it back on under them.
+    #[test]
+    fn an_unticked_structured_view_survives_a_command_change() {
+        let mut draft = DraftPane {
+            picked_cwd: Some(PathBuf::from("/srv/work")),
+            worktree_enabled: false,
+            advanced_collapsed: false,
+            ..DraftPane::default()
+        };
+        draft.set_presets(vec![
+            SpawnPreset {
+                id: "claude".into(),
+                label: "Claude".into(),
+                command: "claude".into(),
+            },
+            SpawnPreset {
+                id: "codex".into(),
+                label: "Codex".into(),
+                command: "codex".into(),
+            },
+        ]);
+        assert!(draft.structured_view);
+
+        draft.toggle_structured_view();
+        assert!(!draft.structured_view);
+
+        draft.cycle_preset(1);
+        assert_eq!(draft.command(), "codex");
+        assert!(
+            !draft.structured_view,
+            "the operator's choice outranks the default"
+        );
+        assert_eq!(draft.build_request().unwrap().view, SessionView::Terminal);
+    }
+
     /// Editing the custom-command text away from a supported agent clears an armed
     /// selection immediately, matching the preset-switch case above — an
     /// invalid `Structured` request can never reach `build_request`.
@@ -2094,7 +2150,7 @@ mod tests {
         };
         draft.selected_preset = draft.presets.len() - 1;
         draft.custom_command = crate::text_input::TextInput::with_value("codex");
-        draft.toggle_structured_view();
+        draft.sync_structured_view();
         assert!(draft.structured_view);
 
         typed(&mut draft, " -p");

docs/STRUCTURED-VIEW.md

@@ -35,6 +35,22 @@ session's worktree holds unsaved work — applies to a structured session
 exactly as it does to a terminal one; only what gets terminated differs (an
 ACP handle instead of a tmux pane).
 
+## Choosing the view
+
+`view` is fixed at spawn and never changes. Every client picks it the same
+way, from the resolved command alone
+(`maestro_protocol::display::supports_structured_view`): a command that
+resolves to Claude Code or Codex spawns **Structured** by default, anything
+else spawns **Terminal**. The operator can override the default — the web and
+TUI spawn forms show the checkbox ticked and let it be unticked, and
+`maestro spawn` takes `--terminal` (or `--structured`, which sends the request
+even for a command the CLI does not recognise and lets the daemon refuse it).
+Once the operator works the toggle, a later command change never re-ticks it
+under them; it can still be forced off when the new command has no adapter.
+
+The daemon is the last word: a `Structured` request for a command with no
+adapter is refused there, whichever client sent it.
+
 ## The adapter
 
 The resolved structured command selects a provider adapter. Its binary is
@@ -302,6 +318,26 @@ pending decision, entirely on the daemon side:
 
 ## Prompt and cancel: bounded liveness
 
+The web composer accepts up to ten files through its attachment picker, file
+drop, or clipboard. Pasted text of at least 4,000 characters or 40 lines becomes
+a UTF-8 `.txt` attachment. Shorter pastes stay in the composer. Attachments can
+be removed before sending; failed sends retain the draft and attachments.
+Pastes also stay inline when all ten attachment slots are occupied or the text
+exceeds the 20 MiB file limit.
+
+On send, `POST /api/sessions/:id/structured/attachments?name=<filename>` uploads
+each file as raw bytes (20 MiB maximum) and returns its absolute `path`.
+Only live structured sessions accept uploads. Filenames are limited to 180
+bytes and cannot contain directory separators or control characters. Files get unique names and private
+file permissions in `<id>.attachments` beside the session sidecar. They persist
+across daemon restarts; removing a composer chip does not delete uploaded data.
+There is currently no automatic attachment cleanup.
+
+The prompt includes each filename and host path so the adapter can read it
+through its own file tools, including images when the provider supports them.
+These references are persisted in the ordinary user transcript row. Attachment
+bytes are not embedded in ACP messages or transcript history.
+
 `POST /api/sessions/:id/structured/prompt` and `.../cancel` are serialized
 against each other through one per-session `operation` lock
 (`AcpEventStream::operation`), because ACP permission callbacks carry no

web/src/api.ts

@@ -184,6 +184,15 @@ export async function sendStructuredPrompt(id: Uuid, prompt: string): Promise<vo
   );
 }
 
+export async function uploadStructuredFile(id: Uuid, file: File): Promise<{ path: string }> {
+  return jsonOrError(await fetch(`${routes.structuredAttachment(id)}?name=${encodeURIComponent(file.name)}`, {
+    method: "POST",
+    credentials: "same-origin",
+    headers: { "content-type": "application/octet-stream" },
+    body: file,
+  }));
+}
+
 /** Cancel a structured session's active ACP turn (#138). */
 export async function cancelStructuredTurn(id: Uuid): Promise<void> {
   await jsonOrError(

web/src/routes.ts

@@ -47,6 +47,10 @@ export function structuredPrompt(id: Uuid): string {
   return `${session(id)}/structured/prompt`;
 }
 
+export function structuredAttachment(id: Uuid): string {
+  return `${session(id)}/structured/attachments`;
+}
+
 /** `POST /api/sessions/:id/structured/cancel` — cancel an ACP turn. */
 export function structuredCancel(id: Uuid): string {
   return `${session(id)}/structured/cancel`;

web/src/spawnForm.ts

@@ -375,13 +375,23 @@ export function createSpawnForm(opts: SpawnFormOptions): SpawnFormHandle {
   // operator has already touched (#76).
   let commandTouched = false;
 
+  // Set once the operator works the checkbox themselves. Until then every
+  // command change re-derives the default (on for Claude Code and Codex, off
+  // for everything else); afterwards their choice outranks it, the same guard
+  // `commandTouched` gives the command field.
+  let structuredTouched = false;
+
   function updateStructuredAvailability(): void {
     const supported = supportsStructuredView(command);
     structuredWrap.hidden = !supported;
     if (!supported) structuredView.checked = false;
+    else if (!structuredTouched) structuredView.checked = true;
   }
 
-  structuredView.addEventListener("change", emit);
+  structuredView.addEventListener("change", () => {
+    structuredTouched = true;
+    emit();
+  });
 
   cmdRaw.addEventListener("input", () => {
     if (selectedPresetId === "custom" || presets.find((p) => p.id === selectedPresetId)?.command === "") {

web/src/spawnFormStructured.test.ts

@@ -44,7 +44,7 @@ describe("spawn form structured view", () => {
     vi.unstubAllGlobals();
   });
 
-  it("is default-off and shown for resolved Claude Code and Codex commands", async () => {
+  it("is default-on and shown for resolved Claude Code and Codex commands", async () => {
     stubApi();
     handle = createSpawnForm({ onSuccess() {} });
     document.body.appendChild(handle.el);
@@ -57,7 +57,7 @@ describe("spawn form structured view", () => {
     handle.el.querySelector<HTMLButtonElement>(".wt-toggle")!.click();
     expect(disclosure.hidden).toBe(false);
     expect(wrap.hidden).toBe(false);
-    expect(checkbox.checked).toBe(false);
+    expect(checkbox.checked).toBe(true);
 
     const custom = handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!;
     custom.click();
@@ -65,13 +65,34 @@ describe("spawn form structured view", () => {
     command.value = "FOO=1 /usr/local/bin/codex";
     command.dispatchEvent(new Event("input"));
     expect(wrap.hidden).toBe(false);
+    expect(checkbox.checked).toBe(true);
 
     command.value = "opencode";
     command.dispatchEvent(new Event("input"));
     expect(wrap.hidden).toBe(true);
+    expect(checkbox.checked).toBe(false);
   });
 
-  it("clears a checked value when Codex changes to an unsupported command", async () => {
+  it("keeps an unchecked box unchecked across a command change", async () => {
+    stubApi();
+    handle = createSpawnForm({ onSuccess() {} });
+    document.body.appendChild(handle.el);
+    await drain();
+
+    const checkbox = handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!;
+    expect(checkbox.checked).toBe(true);
+    checkbox.click();
+    expect(checkbox.checked).toBe(false);
+
+    handle.el.querySelector<HTMLButtonElement>('[data-id="custom"]')!.click();
+    const command = handle.el.querySelector<HTMLInputElement>(".cmd-raw")!;
+    command.value = "codex";
+    command.dispatchEvent(new Event("input"));
+
+    expect(checkbox.checked).toBe(false);
+  });
+
+  it("clears the checked default when Codex changes to an unsupported command", async () => {
     stubApi();
     handle = createSpawnForm({ onSuccess() {} });
     document.body.appendChild(handle.el);
@@ -83,7 +104,6 @@ describe("spawn form structured view", () => {
     command.dispatchEvent(new Event("input"));
 
     const checkbox = handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!;
-    checkbox.click();
     expect(checkbox.checked).toBe(true);
 
     command.value = "opencode";
@@ -93,7 +113,7 @@ describe("spawn form structured view", () => {
     expect(checkbox.checked).toBe(false);
   });
 
-  it.each(["claude", "codex"])("emits Structured for a selected %s command", async (tool) => {
+  it.each(["claude", "codex"])("emits Structured for a %s command by default", async (tool) => {
     const requests = stubApi();
     handle = createSpawnForm({
       seed: { cwd: "/srv/work", cwdRawVisible: true, worktreeEnabled: false },
@@ -109,7 +129,6 @@ describe("spawn form structured view", () => {
       command.dispatchEvent(new Event("input"));
     }
 
-    handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!.click();
     handle.el.requestSubmit();
     await drain();
 
@@ -119,4 +138,21 @@ describe("spawn form structured view", () => {
       view: "Structured",
     });
   });
+
+  it("emits no view once the operator unticks the box", async () => {
+    const requests = stubApi();
+    handle = createSpawnForm({
+      seed: { cwd: "/srv/work", cwdRawVisible: true, worktreeEnabled: false },
+      onSuccess() {},
+    });
+    document.body.appendChild(handle.el);
+    await drain();
+
+    handle.el.querySelector<HTMLInputElement>("input[name=structured_view]")!.click();
+    handle.el.requestSubmit();
+    await drain();
+
+    expect(requests).toHaveLength(1);
+    expect(JSON.parse(String(requests[0].body)).view).toBeUndefined();
+  });
 });

web/src/structured.test.ts

@@ -6,6 +6,7 @@ vi.mock("./api.js", async () => {
   return {
     ...actual,
     sendStructuredPrompt: vi.fn().mockResolvedValue(undefined),
+    uploadStructuredFile: vi.fn().mockResolvedValue({ path: "/uploads/pasted.txt" }),
     cancelStructuredTurn: vi.fn().mockResolvedValue(undefined),
     resolveStructuredApproval: vi.fn().mockResolvedValue(undefined),
     setStructuredConfig: vi.fn().mockResolvedValue(undefined),
@@ -16,6 +17,7 @@ import {
   cancelStructuredTurn,
   resolveStructuredApproval,
   sendStructuredPrompt,
+  uploadStructuredFile,
   setStructuredConfig,
 } from "./api.js";
 import { TOGGLE_DRAWER_EVENT } from "./drawer.js";
@@ -95,6 +97,53 @@ function mount(opts: {
 describe("structured connection: data flow", () => {
   beforeEach(() => vi.clearAllMocks());
 
+  it("converts long pasted text into a removable file and sends it without reply text", async () => {
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const input = conn.el.querySelector("textarea")!;
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: {
+      files: [], getData: () => "a".repeat(4000),
+    } });
+    input.dispatchEvent(paste);
+    expect(paste.defaultPrevented).toBe(true);
+    expect(input.value).toBe("");
+    expect(conn.el.querySelector(".structured-attachments")!.textContent).toContain("pasted-1.txt");
+    conn.el.querySelector("form")!.dispatchEvent(new Event("submit", { cancelable: true }));
+    await vi.waitFor(() => expect(sendStructuredPrompt).toHaveBeenCalledWith("s1", expect.stringContaining("/uploads/pasted.txt")));
+    expect(uploadStructuredFile).toHaveBeenCalledWith("s1", expect.objectContaining({ name: "pasted-1.txt", size: 4000 }));
+    conn.dispose();
+  });
+
+  it("leaves short pastes alone", () => {
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: { files: [], getData: () => "hello" } });
+    conn.el.querySelector("textarea")!.dispatchEvent(paste);
+    expect(paste.defaultPrevented).toBe(false);
+    conn.dispose();
+  });
+
+  it("retains failed uploads for retry and lets the operator remove them", async () => {
+    vi.mocked(uploadStructuredFile).mockRejectedValueOnce(new Error("Upload failed"));
+    const conn = mount({ sockets: [new FakeSocket()] });
+    const input = conn.el.querySelector("textarea")!;
+    input.value = "Read this";
+    const paste = new Event("paste", { bubbles: true, cancelable: true });
+    Object.defineProperty(paste, "clipboardData", { value: {
+      files: [new File(["content"], "notes.txt")], getData: () => "",
+    } });
+    input.dispatchEvent(paste);
+    conn.el.querySelector("form")!.dispatchEvent(new Event("submit", { cancelable: true }));
+    await vi.waitFor(() => expect(input.disabled).toBe(false));
+    expect(input.value).toBe("Read this");
+    expect(sendStructuredPrompt).not.toHaveBeenCalled();
+    const remove = conn.el.querySelector<HTMLButtonElement>('[aria-label="Remove notes.txt"]')!;
+    expect(remove).not.toBeNull();
+    remove.click();
+    expect(conn.el.querySelector<HTMLElement>(".structured-attachments")!.hidden).toBe(true);
+    conn.dispose();
+  });
+
   it("renders every row from the initial snapshot", () => {
     const ws = new FakeSocket();
     const conn = mount({ sockets: [ws] });

web/src/structured.ts

@@ -10,6 +10,7 @@ import {
   cancelStructuredTurn,
   resolveStructuredApproval,
   sendStructuredPrompt,
+  uploadStructuredFile,
   setStructuredConfig,
   structuredWsUrl,
 } from "./api.js";
@@ -90,7 +91,12 @@ export function createStructuredConnection(
           <span class="structured-activity-text">Thinking</span>
         </div>
         <form class="structured-composer">
+          <button type="button" class="btn btn-ghost btn-icon structured-attach" aria-label="Attach files" title="Attach files (up to 20 MiB each)">
+            <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.5" aria-hidden="true"><path d="m8 12 7-7a3 3 0 0 1 4 4L9 19a5 5 0 0 1-7-7L12 2M5 14l9-9"/></svg>
+          </button>
+          <input class="structured-file-input" type="file" multiple hidden>
           <div class="structured-input-wrap">
+            <div class="structured-attachments" aria-label="Attachments" aria-live="polite" hidden></div>
             <div id="structured-command-menu-${sessionId}" class="structured-command-menu"
               role="listbox" hidden></div>
             <textarea class="structured-input" rows="1" placeholder="Reply, or / for commands…"
@@ -128,6 +134,79 @@ export function createStructuredConnection(
   const input = el.querySelector(".structured-input") as HTMLTextAreaElement;
   const sendBtn = el.querySelector(".structured-send") as HTMLButtonElement;
   const cancelBtn = el.querySelector(".structured-cancel") as HTMLButtonElement;
+  const attachBtn = el.querySelector(".structured-attach") as HTMLButtonElement;
+  const fileInput = el.querySelector(".structured-file-input") as HTMLInputElement;
+  const attachmentEl = el.querySelector(".structured-attachments") as HTMLDivElement;
+  type Attachment = { file: File; path?: string };
+  let attachments: Attachment[] = [];
+  let uploading = false;
+  let pasteCount = 0;
+
+  function renderAttachments(): void {
+    attachmentEl.replaceChildren();
+    attachmentEl.hidden = attachments.length === 0;
+    for (const attachment of attachments) {
+      const chip = document.createElement("span");
+      chip.className = "structured-attachment";
+      const label = document.createElement("span");
+      label.textContent = attachment.file.name;
+      label.title = `${attachment.file.name} (${attachment.file.size.toLocaleString()} bytes)`;
+      const remove = document.createElement("button");
+      remove.type = "button";
+      remove.textContent = "×";
+      remove.setAttribute("aria-label", `Remove ${attachment.file.name}`);
+      remove.disabled = input.disabled;
+      remove.addEventListener("click", () => {
+        attachments = attachments.filter((item) => item !== attachment);
+        renderAttachments();
+      });
+      chip.append(label, remove);
+      attachmentEl.append(chip);
+    }
+  }
+
+  function addFiles(files: File[]): void {
+    if (input.disabled || disposed) return;
+    for (const file of files) {
+      if (file.size > 20 * 1024 * 1024) {
+        showError(`${file.name} exceeds 20 MiB. Choose a smaller file.`);
+      } else if (attachments.length >= 10) {
+        showError("Attach up to 10 files per message.");
+      } else {
+        attachments.push({ file });
+      }
+    }
+    renderAttachments();
+  }
+  attachBtn.addEventListener("click", () => fileInput.click());
+  fileInput.addEventListener("change", () => {
+    addFiles(Array.from(fileInput.files ?? []));
+    fileInput.value = "";
+  });
+  composerForm.addEventListener("dragover", (event) => {
+    if (event.dataTransfer?.types.includes("Files")) event.preventDefault();
+  });
+  composerForm.addEventListener("drop", (event) => {
+    if (!event.dataTransfer?.files.length) return;
+    event.preventDefault();
+    addFiles(Array.from(event.dataTransfer.files));
+  });
+  input.addEventListener("paste", (event) => {
+    const clipboard = event.clipboardData;
+    if (!clipboard || input.disabled) return;
+    if (clipboard.files.length) {
+      event.preventDefault();
+      addFiles(Array.from(clipboard.files));
+      return;
+    }
+    const text = clipboard.getData("text/plain");
+    if (text.length < 4000 && text.split("\n").length < 40) return;
+    if (attachments.length >= 10 || new Blob([text]).size > 20 * 1024 * 1024) return;
+    event.preventDefault();
+    addFiles([new File([text], `pasted-${++pasteCount}.txt`, { type: "text/plain" })]);
+    input.setRangeText("", input.selectionStart, input.selectionEnd, "end");
+    autoResize();
+  });
 
   disconnectBtn.addEventListener("click", () => opts.onRequestClose?.(sessionId));
   // Mobile-only (CSS hides it on desktop, where the sidebar is always in
@@ -527,9 +606,12 @@ export function createStructuredConnection(
   }
 
   function renderComposerState(): void {
-    const active = state.turn.responding || state.turn.thinking || awaitingBeginGeneration !== null;
+    const active = uploading || state.turn.responding || state.turn.thinking || awaitingBeginGeneration !== null;
     const projectedActive = state.turn.responding || state.turn.thinking;
     input.disabled = active;
+    attachBtn.disabled = active;
+    fileInput.disabled = active;
+    renderAttachments();
     sendBtn.disabled = active;
     sendBtn.hidden = projectedActive;
     cancelBtn.hidden = !projectedActive;
@@ -797,7 +879,9 @@ export function createStructuredConnection(
   composerForm.addEventListener("submit", (e) => {
     e.preventDefault();
     const text = input.value;
-    if (!text.trim() || input.disabled) return;
+    if ((!text.trim() && attachments.length === 0) || input.disabled) return;
+    const submittedAttachments = attachments;
+    uploading = submittedAttachments.length > 0;
     const generation = ++submissionGeneration;
     const submissionSocketGeneration = socketGeneration;
     awaitingBeginGeneration = generation;
@@ -807,13 +891,26 @@ export function createStructuredConnection(
     autoResize();
     clearError();
     renderComposerState();
-    sendStructuredPrompt(sessionId, text).then(
+    const send = async () => {
+      for (const attachment of submittedAttachments) {
+        if (disposed) return;
+        if (!attachment.path) attachment.path = (await uploadStructuredFile(sessionId, attachment.file)).path;
+      }
+      if (disposed) return;
+      const references = submittedAttachments.map(({ file, path }) =>
+        `Attached file ${JSON.stringify(file.name)}: ${JSON.stringify(path)}`);
+      await sendStructuredPrompt(sessionId, [text, ...references].filter(Boolean).join("\n\n"));
+    };
+    void send().then(
       () => {
-        if (
-          disposed
-          || generation !== submissionGeneration
-          || awaitingBeginGeneration !== generation
-        ) return;
+        if (disposed || generation !== submissionGeneration) return;
+        uploading = false;
+        if (attachments === submittedAttachments) {
+          attachments = [];
+          renderAttachments();
+        }
+        renderComposerState();
+        if (awaitingBeginGeneration !== generation) return;
         const acceptanceSocketGeneration = socketGeneration;
         acceptedSubmission = { generation, socketGeneration: acceptanceSocketGeneration };
         // A replacement socket may have captured idle before the POST claimed
@@ -821,6 +918,7 @@ export function createStructuredConnection(
         if (acceptanceSocketGeneration > submissionSocketGeneration) reconnectForReconciliation();
       },
       (e: unknown) => {
+        uploading = false;
         if (disposed || generation !== submissionGeneration) return;
         if (awaitingBeginGeneration === generation) awaitingBeginGeneration = null;
         if (input.value === "") {

web/src/styles.css

@@ -3088,6 +3088,45 @@ input.leaf-rename:focus {
   min-width: 0;
 }
 
+.structured-attachments {
+  display: flex;
+  flex-wrap: wrap;
+  gap: var(--sp-1);
+  padding: var(--sp-1);
+}
+
+.structured-attachments[hidden] { display: none; }
+
+.structured-attachment {
+  display: inline-flex;
+  align-items: center;
+  min-width: 0;
+  max-width: 100%;
+  padding-left: var(--sp-2);
+  background: var(--surface-2);
+  border: 1px solid var(--border);
+  border-radius: var(--r-1);
+  font-size: var(--fs-11);
+}
+
+.structured-attachment > span {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.structured-attachment button {
+  flex-shrink: 0;
+  min-width: var(--tap);
+  min-height: var(--tap);
+  border: 0;
+  background: transparent;
+  color: var(--muted);
+}
+
+.structured-attachment button:hover { color: var(--ink); }
+.structured-attachment button:disabled { opacity: 0.5; }
+
 .structured-input {
   display: block;
   width: 100%;